Functionalized NaA nanozeolites labeled with 224,225Ra for targeted alpha therapy

Abstract

The 223Ra, 224Ra, and 225Ra radioisotopes exhibit very attractive nuclear properties for application in radionuclide therapy. Unfortunately the lack of appropriate bifunctional ligand for radium is the reason why these radionuclides have not found application in receptor-targeted therapy. In the present work, the potential usefulness of the NaA nanozeolite as a carrier for radium radionuclides has been studied. 224Ra and 225Ra, α-particle emitting radionuclides, have been absorbed in the nanometer-sized NaA zeolite (30–70 nm) through simple ion exchange. 224,225Ra-nanozeolites exhibited very high stability in solutions containing physiological salt, EDTA, amino acids, and human serum. To make NaA nanozeolite particles dispersed in water their surface was modified with a silane coupling agent containing poly(ethylene glycol) molecules. This functionalization approach let us covalently attach a biomolecule to the NaA nanozeolite surface.

Synthesis and characterization of lanthanum phosphate nanoparticles as carriers for 223Ra and 225Ra for targeted alpha therapy

“…The in vivo generators 223 Ra, 224 Ra, and 225 Ra are also promising candidates for TAT [16][17][18][19][20][21][22]. Similar to 225 Ac, during the decay of 223 Ra and 225 Ra, ~28 MeV of energy is released and ~90-94% of this energy is associated with four sequentially emitted α-particles ( Fig.…”

“…Investigations of the potential usefulness of liposomes with a diameter of ~120 nm showed retention of 223 Ra up to 93% after 4.2 d in serum [16,17]. Also, recent work on the use of the NaA nanozeolite particles of ~100 nm to carry Ra radionuclides has been reported [19].…”

An overview of nanoscale radionuclides and radiolabeled nanomaterials commonly used for nuclear molecular imaging and therapeutic functions

“…So, the zeolite nanostructures with different selectivities can act as the ion-exchanger. Piotrowska et al 94 proposed the use of nanozeolite whose channels and cavities were filled with cations of 224 Ra and 225 Ra by means of simple ion exchange without any additional operations. The 223 Ra, 224 Ra, and 225 Ra radioisotopes exhibit very attractive nuclear properties for application in radionuclide therapy.…”

“…Unfortunately, the lack of appropriate bifunctional ligands for radium is the reason why these radionuclides have not found application in receptor-targeted therapy. 94 These α-particle emitting radionuclides were absorbed in the nanometer-sized NaA zeolite (30-70 nm) through simple ion exchange. 224 Ra and 225 Ra radiolabeled nanozeolites exhibited very high stability in human serum.…”

Targeted and Nontargeted α-Particle Therapies

“…Daughter retention (up to 88%) increased with additional gadolinium phosphate shells. Interestingly, Piotrowska et al (102) found that the first daughter of 225 Ac, 221 Fr, was well retained by biocompatible crystalline aluminosilicate nanozeolites (40 to 120 nm in diameter) when radiolabeled with 225 Ra. These constructs also stably retained 225 Ac in the presence of ethylene-diaminetetraacetic acid (≤5.5 ± 2.5% release) and in human blood serum (≤2.3 ± 1.9%).…”